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Glucose-responsive microgels integrated with enzyme nanocapsules for closed-loop insulin delivery
Zhen Gu1, Tram T Dang, Minglin Ma
1Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
ACS Nano
|July 10, 2013
Summary
Researchers developed injectable microgels for type 1 diabetes treatment. These glucose-responsive microgels control insulin release, effectively lowering blood glucose levels in diabetic mice.
Area of Science:
- Biomaterials Science
- Endocrinology
- Drug Delivery Systems
Background:
- Type 1 diabetes mellitus (T1DM) management requires precise glucose control.
- Closed-loop insulin delivery systems offer a promising therapeutic approach.
- Current systems face challenges in achieving physiological glucose responsiveness.
Purpose of the Study:
- To develop uniform, injectable, glucose-responsive microgels for controlled insulin delivery.
- To encapsulate enzymes within nanocapsules for enhanced stability and controlled release.
- To evaluate the efficacy of the microgel system in a mouse model of T1DM.
Main Methods:
- Fabrication of monodisperse microgels using a one-step electrospray procedure.
- Covalent encapsulation of glucose-specific enzymes into nanocapsules within a chitosan matrix.
- Assessment of microgel swelling and insulin release under varying glucose concentrations.
- In vivo evaluation of the system's efficacy in a mouse model of T1DM.
Main Results:
- Uniform microgels (256 ± 18 μm) were successfully fabricated.
- Enzyme nanocapsules enhanced enzyme stability and prevented diffusion.
- Microgels exhibited glucose-responsive swelling and tunable insulin release rates.
- The system demonstrated significant reduction in blood glucose levels in diabetic mice.
Conclusions:
- Injectable, glucose-responsive microgels with enzyme nanocapsules offer a viable strategy for T1DM treatment.
- The system acts as a self-regulating valve, releasing insulin based on glucose levels.
- This approach holds potential for improving glycemic control and patient outcomes in T1DM.
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